I have two meer lined Kaywoodies. One is sweet, the other was filled with years of tar in the shank and I'm still cleaning this one. I am hoping the dirty one will smoke as well as the first after it is clean.
So far I've used over 40 Q-tips with 91% iso alcohol and it is still very dirty. I tend to get discouraged because my cheapy Q-tips keep losing the cotton part in the shank, and I had to bend a thin wire to remove the cotton. I am avoiding using a retort because I know you should avoid alcohol in a meer.
I also have two fairly good meerschaums, one is an I Becker CAO, the other is from S Yanik. I like the kaywoodie as much as either of these meers.